the track team is trying to reduce their time for a relay race. First they reduce their time by 2.1 minutes. then they are able to reduce their time by 1/10. If their final time is 3.96 minutes what was their beginning time?

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WaywardDelaney WaywardDelaney · Answer 1 · 2020-01-13T16:33:56+01:00

Answer:

The beginning time of relay race is 6.73 minutes

Step-by-step explanation:

Given as :

The final time of relay race = 3.96 minutes

Let The initial time of relay race = x minutes

At first, The time reduce by 2.1 min

So, The first time become = ( x - 2.1 ) min

At second , The time reduce by [tex]\dfrac{1}{10}[/tex] = 0.1

So, The time become = ( x - 2.1 ) min - [tex]\dfrac{x}{10}[/tex] min

[tex]\dfrac{10 (x - 2.1) - x}{10}[/tex]

Or, [tex]\dfrac{9 x - 21}{10}[/tex]

∵ final time of race = 3.96 min

∴ [tex]\dfrac{9 x - 21}{10}[/tex] = 3.96

Or, 9 x - 21 = 3.96 × 10

Or, 9 x = 39.6 + 21

Or, 9 x = 60.6

∴ x = [tex]\dfrac{60.6}{9}[/tex]

i.e x = 6.73 minutes

So, The beginning time = x = 6.73 min

Hence,The beginning time of relay race is 6.73 minutes Answer